Updated: 23 September 2026 · EuroVan Shop
In short: To fit a skylight in a campervan, check that your roof thickness is within the model's range, mark and cut the exact cut-out (400 × 400, 700 × 500 or 960 × 655 mm), clean with Activator 205, prime with Primer 507, fill corrugations with 831E butyl tape, bed the frame in Sikaflex 552 AT and screw the interior frame. Our Sikaflex skylight pack has all four products.
Choose your roof windowCan you fit a campervan skylight yourself?
Yes: fitting a skylight is a realistic DIY job with a jigsaw, a cordless drill/driver and the right sealant. Our roof windows mount directly on flat or corrugated roofs, so there is no adaptor frame to build on a corrugated panel.
Plan a dry day and a helper. Two people are needed to lower a PANORAMA SLIM 3 LED into the cut-out, and a first VANVENT 3.0 fit takes about two hours. The job itself is the same for every model: measure, cut, prepare, seal, fix and test.
What do you need to fit a skylight?
You need the skylight, the Sikaflex skylight pack, a jigsaw, a cordless drill/driver and a cartridge gun. The rest is ordinary workshop kit.
- Sikaflex skylight pack: Sikaflex 552 AT adhesive sealant (300 ml, white), Sika Activator 205, Sika Primer 507 and SikaLastomer 831E butyl tape.
- To apply it: a cartridge gun, a clean lint-free cloth for the Activator 205 and a brush for the Primer 507.
- To cut: a jigsaw with a metal blade, a drill for the corner holes, masking tape, a tape measure, a pencil and a file.
- For a fan: a 12 V supply on a fused circuit (5 A fuse recommended for the VANVENT 3.0).
Not sure which sealant does what? Our Sikaflex guide explains each product.
Check the cut-out and roof thickness first
Before you cut, check two figures: the cut-out of your skylight and the roof thickness it accepts. The frame clamps the roof between the outer unit and the interior frame, so measure the total thickness at the edge of the opening, from the outer skin to the finished ceiling.
| Model | Cut-out (mm) | Roof thickness | Height above roof |
|---|---|---|---|
| EuroVan 28x28 | 280 × 280 | 25–50 mm | – |
| POWER VENT | 280 × 280 or 320 × 320 | 25–80 mm | – |
| EuroVan 36x36 | 360 × 360 | 25–60 mm | – |
| SKYDOME 40x40 | from 385 × 385 | – | – |
| STYLE 40x40 | 400 × 400 | 28–70 mm | 12 cm |
| EuroVan 40x40 | 400 × 400 | 25–60 mm | – |
| VANVENT 3.0 | 400 × 400 | 27–80 mm | 127 mm closed |
| PANORAMA LED 50x70 | 700 × 500 | 25–75 mm (more with a spacer) | about 12 cm |
| PANORAMA SLIM 3 LED | 500 × 500, 700 × 500, 800 × 500, 960 × 655 | 25–70 mm | 6 cm |
A dash means the figure is not on the product sheet: send us your measurements before you order. Outside the range? Contact us before cutting anything.
Where should you put a skylight in a van?
Put the skylight on a clear area of the roof, between the crossmembers: check that no roof crossmember runs through the chosen spot. Look inside too, because the interior frame is larger than the hole. On the STYLE 40x40, allow up to 130 mm more in width and 110 mm more in height for the interior frame.
- A roof window over the living area or bed gives the most daylight.
- A 12 V fan over the kitchen or shower clears steam where it is produced.
- Keep clear of roof racks, solar panels and cable runs.
How to fit a campervan skylight, step by step
Work in this order and do not skip the preparation: most leaks come from a dirty surface or a broken bead, not from the skylight.
- Mark the cut-out on the roof to the exact size stated for your model, and tape around it to protect the paint.
- Drill the corners from outside, then cut along the lines with the jigsaw.
- File and clean the edges, remove all swarf and protect bare metal against rust.
- Clean the bonding area with Sika Activator 205 on a lint-free cloth.
- Apply Sika Primer 507 with a brush and let it flash off as Sika's instructions state.
- On a corrugated roof, lay SikaLastomer 831E butyl tape in the ridges so the frame sits on an even base.
- Run a continuous bead of Sikaflex 552 AT around the frame, with no gaps at the corners.
- Lower the skylight into the cut-out (two people for a large one) and press it down evenly.
- Fit the interior frame from inside with the supplied screws, tightening evenly without distorting it.
- Wipe off excess sealant, then water-test once the curing time stated by Sika has passed.
Can you fit a skylight on a corrugated van roof?
Yes: our roof windows and fans mount directly on a corrugated roof, and SikaLastomer 831E butyl tape fills the ridges. You do not need an adaptor frame, and direct fitting means fewer joints that could leak over the years.
Choose a spot where the corrugations run cleanly under the whole frame, lay the butyl across the ridges, then bond with Sikaflex 552 AT as on a flat roof. Butyl seals; the 552 AT holds.
Fitting a 12 V roof vent fan: wiring and power
A roof vent fan fits exactly like a roof window, plus a 12 V supply on a fused circuit. Run the cable before you close the ceiling.
- VANVENT 3.0: 12 V DC (9–16 V), 20 W fan + 4 W LED, 5 A fuse recommended. On 24 V, add a 24 V to 12 V converter.
- EuroVan 40x40 and 36x36: a 12 V feed for the reversible fan.
- EuroVan 28x28: a single 12 V feed powers both the fan and the LED.
- POWER VENT: a fused 12 V supply; the dome opens by crank, so it still opens and closes with the power off.
Replacing a caravan or motorhome skylight: the short version
On a caravan or motorhome, the hole already exists, so you keep it and fit a skylight made for the same cut-out. Measure the opening in the roof, not the outer frame of the old skylight.
- Unscrew the interior frame and lift the old skylight out.
- Remove every trace of old sealant, then clean and degrease the roof.
- Pick the same cut-out: 400 × 400 mm, 700 × 500 mm or 960 × 655 mm.
- Prepare with Activator 205 and Primer 507, bed in Sikaflex 552 AT, fit and test as above.
For each step in detail, read how to replace a caravan or motorhome skylight, or browse our 40 x 40 skylights and Heki-size roof windows. Heki is a trademark of Dometic.
Do you need approval to fit a skylight?
It depends on your country, so check your national rules (DVLA in the UK, TÜV in Germany, RDW in the Netherlands) before you cut. The STYLE 40x40, PANORAMA SLIM 3 LED, PANORAMA LED 50x70 and VANVENT 3.0 are ECE R43 approved. Permanent ventilation is often asked for when a conversion is approved, which is why several of our roof windows have it built in.
Not sure which roof window fits your roof?
Send us the cut-out size and roof thickness (or a photo). Our France-based technical team answers within 24 hours.
Ask our technical teamFrequently asked questions
Can I install a skylight myself?
Yes. With a jigsaw, a cordless drill/driver and the Sikaflex skylight pack, fitting a roof window is a realistic DIY job. Plan two people for a large PANORAMA.
What is the best sealant for a campervan skylight?
Sikaflex 552 AT, after cleaning with Sika Activator 205 and priming with Sika Primer 507. On a corrugated roof, add SikaLastomer 831E butyl tape to fill the ridges. All four are in our Sikaflex skylight pack.
Do I need a frame to fit a skylight on a corrugated roof?
Not with our roof windows: they mount directly on the roof, and the 831E butyl tape fills the ridges without an adaptor frame.
How long does it take to fit a skylight?
Allow about two hours for a first VANVENT 3.0 fit, plus the curing time stated by Sika before the water test.
What roof thickness do I need?
It depends on the model: 28 to 70 mm for the STYLE 40x40, 25 to 70 mm for the PANORAMA SLIM 3 LED, 27 to 80 mm for the VANVENT 3.0 and 25 to 80 mm for the POWER VENT.
Cut-out and roof thickness measured? Pick your roof window.
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